1. Field of the Invention
The present invention relates to the packaging of circuit chips and more particularly to providing a method of assembly and an apparatus for cooling circuit chip packages.
2. Description of Related Art
U.S. Pat. No. 6,292,369 describes a thermally conductive lid structure having a customized lid understructure and shim. This structure uses thermally conductive compliant or non-rigid materials in the primary heat dissipation path.
U.S. Patent Publication 2008-0165502, describes a patterned metal deformable thermal interface placed between a circuit chip and a heat dissipative structure to improve the quality of the heat dissipation path.
To reduce the stress placed on package elements resulting from temperature changes through various assembly steps and operation of the package, U.S. Pat. No. 5,821,617 teaches enhancing performance by providing a package which uses materials that are matched in CTE to each other and to a silicon circuit chip. This is because using different coefficients of thermal expansion (CTEs) of the materials of the package components increases stress. Accordingly, the use of materials having different coefficients of thermal expansion (CTEs) is discouraged by the industry, as taught by U.S. Pat. No. 5,821,617. Thus, there is a need for a package that provides good thermal coupling between a chip and a heat spreader or heat sink through excursions in the temperature of the package.